(1) Field of the Invention
The present invention refers to a sear mechanism for firearms.
(2) Description of Related Art
In general, the field of portable, semi-automatic or automatic firearms foresees different solutions for the sear mechanism, which comprises a mobile element which holds the hammer in the cocking position.
Following the voluntary pulling of the trigger, the mobile element frees the hammer and allows it to hit against a firing pin under the thrust of a preloaded elastic element.
Such a mobile element can be realised, for example as a sear or as a sear pawl, pivoted at a fixed part of the body of the firearm and biased by an elastic element. To carry out its function such a mobile element is thus is engagement with both the trigger and with the hammer.
Such a mobile sear element constitutes a delicate detail of the sear mechanism, since it is stressed mechanically and has a complex form, and it is thus generally made from metal.
Since the hammer and the sear element are equipped with additional engagement teeth, due to problems of wear of the interfacing contact surfaces, the hammer must also necessarily be made from metal.
Hereafter specific reference shall be made to a rifle, even though that which is object of the invention can be applied to all firearms, including side-by-side, semi-automatic, rifled and military ones, etc.
Moreover, given that the invention is intended for experts in the field of firearms, it is omitted the detailed description of the structure and operation of a firearm, in particular of a rifle like the one described. It is just given a reminder of the functions of the firearm parts involved in the technical problem forming the basis of the invention.
Therefore, a purpose of the present invention is that of overcoming the limits of the state of the art, trying to achieve a configuration of the sear mechanism for firearms which is simple and reliable.
Another purpose of the present invention is that of realising a sear mechanism which is lighter and possibly comprising elements made from plastic.
A purpose inherent to the previous ones is that of being able to have low actuation forces and limited wear.
Yet another purpose of the present invention is that of being able to have great cost-effectiveness of construction and simplicity of assembly.
These purposes according to the present invention are accomplished by realising a sear mechanism for firearms which comprises a sear box (12), a trigger (15) mounted at said sear box (12) on a rotation pin (18) and upon which acts an elastic return element (25), a hammer (16) mounted at said sear box (12) on a pin of the hammer (31, 31xe2x80x2) and upon which acts an elastic thrust element (33), in which said hammer (16) is equipped with a mounting tooth (40) for the engagement with a sear tooth (41), and a breechblock carrier (13) carrying a firing pin (14), as well as comprising a sear device (17, 17xe2x80x2) to give said hammer (16), when controlled by said trigger (15), motion between a cocking position (A) in engagement with said sear tooth (41) and a striking position (B) against said firing pin (14), characterised in that said sear tooth (41) is fixed and integral with said sear box (12), said pin of the hammer (31, 31xe2x80x2) is in engagement with a slot (32) of said sear box (12) and in that said sear device (17, 17xe2x80x2) comprises at one end an engagement element (43, 56) with said pin of the hammer (31, 31xe2x80x2) suitable for causing it to advance in said slot (32), said motion between said cocking position (A) and said striking position (B) of said hammer (16) being made up of an initial translation step and a subsequent rotary step under the action of said elastic thrust element (33), said sear device (17, 17xe2x80x2) being connected at an opposite end thereof to said trigger (15).
The characteristics and advantages of a sear mechanism for firearms according to the present invention shall become clearer from the following description, given as an example and not for limiting purposes.